The -memref-dataflow-opt pass (lib/Transforms/MemRefDataFlowOpt.cpp) hasn’t been located at the right place from the start. A couple of things about it.
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The pass really works on affine ops on memrefs and also makes use of affine dependence information. This should ideally have been in
lib/Dialect/Affine/Transformslike other affine passes there. It really doesn’t depend on on anything more than what other affine passes use. -
This pass really replaces subscripted affine memref accesses with scalars and is thus more accurately a scalar replacement pass. Besides store to load forwarding, it can eliminate redundant loads: in all these cases, subscripted memref accesses get replaced by (scalar) SSA values. It’s not really a memref dataflow analysis/opt which can be far more general.
I propose to move this under lib/Dialect/Affine/Transforms and rename it AffineScalarReplacement.cpp (-affine-scalrep). It’ll thus become part of MLIRAffineTransforms instead of MLIRTransforms.